I don't know if my answer is completely correct, but I think it's 100. All triangles add up to 180, and an isosceles triangle has 2 equal sides. 40 would be the 2 sides, and 180 subtracted from 80 equals 100.
D)30 us 6 times as many as 5 and 5 times as many as 6.
Answer:
Step-by-step explanation:
I've enclosed a graph to show you that there is one solution.
-4x + 3y = - 12
<u>- 2x + 3y = - 18</u><em><u> </u></em><em> </em>Subtract
-2x = 6 Divide by - 2
-2x/-2 = 6/-2
x = - 3
- 4x + 3y = - 12
-4(-3) + 3y = - 12
12 + 3y = - 12
3y = - 12 - 12
3y = - 24
3y/3 = - 24/3
y = - 8
Which is exactly what the graph shows.
You can tell immediately that this has 1 or more solutions just by looking at the number in front of x and y in each each equation.
It's always a good idea to graph a question like this one. Desmos is a pretty good tool to use if you don't have a graphing calculator.
The y's are the same so you are 1/2 way home in saying what you did.
The x's are different so that means you have at least 1 solution.
Say Terry read at the rate of 75 pages per day for d days.
Now, in d days she read 75d pages, and since after that 690 pages were left, then the number of pages in the book is 75d+690.
Next, we also know that she had d+6 days for the assignment. Since Terry planned to read 90 pages per day for this number of days, then the number of pages in book is also equal to 90(d+6).
So, we have that 75d+690 = 90(d+6). Solving the linear equation, we get d = 10.
Thus, the total number of days that she has to complete the assignment on time is d+6 or 10 + 6 = 16 days.
Answer: Nickels x = 11 and pennies y = 9
Step-by-step explanation:
Let be nickels x and pennies y
We will form a system to solve this problem:
5 x + 1 y = 64
x + y = 20/ · (-1)
we will first multiply the second equation by -1 and add it by the first and get:
4 x = 44 ⇒ x = 44 / 4 = 11 nickels
x = 11 nickels
from the other we get y
y = 20 - x = 20 - 11 = 9 pennies
y = 9 pennies
